Eno,

I was using the older style header until the middle of last year. The newer style definitely gives more rpm. But, I was having a lot of trouble with header coming loose, even broke two of the nut by over tightening. Therefore, returned to using the older style again, and the carbon problem became real severe. I have since solved the mounting problem with the help from the list and Al Coomber from Central Hobbies. However, the carbon buildup seems to persist.

I think once you have carbon on the valves, it will continue to build until de-carbonized, there is no way you can just clean the header. I was thinking of using Magnum # 1 with lesser oil percentage, but Verano told me both the 140 and 160 DZ runs better with higher oil percentage.

Don't get me wrong, I wasn't trying to blame any manufacturer, just trying to solicit suggestions.

Thank you all for the reply.

Adrian